Proving that people love cheap computers, the $25 Raspberry Pi PC is impossible to buy, just hours after going on sale.

The Raspberry Pi is a $25 computer board, the size of a credit card, with no frills. It runs Linux-based operating systems, and comes without a case, keyboard or monitor. Its jacks and ports protrude from the tiny green motherboard.

Two versions are available: the $25 Model A and the $35 Model B. Both have a 700 MHz ARM11 processor, 256 MB of RAM and ports for USB, HDMI, SD, RCA video and 3.5 mm audio. The more expensive Model B has an Ethernet jack and two USB slots instead of one.

The Raspberry Pi Foundation created the computers with the goal of getting children interested in computer science and programming. Whatever small profit the group makes from Raspberry Pi, it puts back into the charity.

But first, the Foundation is putting Raspberry Pi in the hands of enthusiasts. And that’s where things have gotten a little out of hand. As OSNews reports, the websites for both retailers who were selling the Raspberry Pi–Premier Farnell and RS Components–crashed shortly after the launch at 7:00 Central European Time.

Both sites are back online now, but Premier Farnell has already sold out of its first batch. RS is taking sign-up details for further ordering instructions, but according to Engadget, the retailer is only shipping within the United Kingdom.

Raspberry Pi’s website says people will be able to place batch orders in about a month, so hopefully folks who want a cheap Linux box for tinkering will have no problem getting one then.